My grandmother left me a sterling coffee/tea set, and all of the pieces have this mark. The family believes it to be Reed & Barton, but I don't see these marks anywhere and it I can't find it on this site anywhere. I presume the "U.S" to be "United States", but I don't understand why there wouldn't be a mark for the manufacturer, if that's the case. All of the pieces look like this, although some also have a "16" on top of the mark, and some have "13" instead of "12". But they all have the "U.S." Can anyone help?

Thanks,
Warren

